Thank you for contacting Intel Embedded Community.
The information that may help you is stated in section 2.16 of the Intel(R) 64 and IA-32 architectures software developer's manual volume 4: Model-specific registers document # 335592.
We hope that this information may help you.
Hi Carlos_A ,
it is not helpful. Mentioned document doesnt' contain information about MSR 121H (aka 0x121). This is MSR with ACPI Timer Emulation bit inside.
Please consult experts and point me to correct document.